I took for this sound 4 different machine sounds: a wood milling machine, a heavy bulldozer sound, a drilling machine and some heavy beating sounds with a hammer. I convoluted the four sounds to create one single drone of over one minute long. I placed this sound within Kontakt 4 and used the time machine 2 mode to pitch the sound and there you have the Industrial drone layer sound. A mellow drone like soundscape... suitable as background noise. Created within Cubase 5.